Investigators think the boy, who had turned three the day before, wandered outside sometime during the night and may have died as a result of exposure to the cold. Overnight wind chill values were below zero.

“When you come to a tragic situation like this, it is always heartbreaking for everybody involved, including the officers investigating the case,” said Burke County Sheriff Steve Whisenant. “So our prayers go out to all the families.”

Investigators say the front door was unlocked, but the boy may have been unable to open the storm door when it closed after him.

The child’s mother and her boyfriend were asleep inside at the time of the incident, deputies told WSOC.